U.S. Pat. No. 4,299,012 discloses a conventional hose clamp. The inner surface of this hose clamp, in the tightened condition, is free of gaps and steps; therefore, it supports the hose at all locations of its periphery. As a result, the known clamp has been found suitable for mounting thin, hard hoses to pipe nipples.
For connecting the outer band end with the inner band portion, the known hose clamp has a guide hook and at least one holding or support hook disposed on the inner band portion. In the closed condition, each of the guide and support hooks engages a window formed in the outer band portion.
In hoses of decreasing thickness and elasticity and with the correspondingly increasing tightening forces required, the hook connection becomes a weak point. Thus, the window next to the tightening means, which may be a so-called “Oetiker-ear”, tends to extend and finally tear under excessive forces. This problem may be overcome by using a more elastic higher quality steel but this increases cost.